Training, Open Source computer languages
PerlPHPPythonMySQLApache / TomcatTclRubyJavaC and C++LinuxCSS 
Search for:
Home Accessibility Courses Diary The Mouth Forum Resources Site Map About Us Contact
 
For 2023 (and 2024 ...) - we are now fully retired from IT training.
We have made many, many friends over 25 years of teaching about Python, Tcl, Perl, PHP, Lua, Java, C and C++ - and MySQL, Linux and Solaris/SunOS too. Our training notes are now very much out of date, but due to upward compatability most of our examples remain operational and even relevant ad you are welcome to make us if them "as seen" and at your own risk.

Lisa and I (Graham) now live in what was our training centre in Melksham - happy to meet with former delegates here - but do check ahead before coming round. We are far from inactive - rather, enjoying the times that we are retired but still healthy enough in mind and body to be active!

I am also active in many other area and still look after a lot of web sites - you can find an index ((here))
Expect - bad command trap

Posted by sgy258 (sgy258), 13 January 2004
I have an existing expect program that is used to spawn a telnet session and automatically login a user to a server. I would like to trap certain commands to prevent users from executing those commands (passwd, etc.). I modified my program according to Don Libes "Exploring Expect" Preventing - Bad Commands example on page 347.

The command trap works, however when a user types a string, the string is echoed back on the next line - example:

guest@gumby> pwd
pwd
/export/home

Is there a way to prevent the string from echoing a new line with the command?

Here is the section of code:

set prompt ">"
set badcmds "passwd|su"

interact {
-o -reset -nobuffer -re $prompt {
while 1 {
set timeout 1800
expect_user {
-re "^badcmds.*"
{
send_user "Command not allowed...!\n"
sleep 3
break
}
-re "(.*)\n"
{
send "$expect_out(1,string)\r"
break
}
timeout {
exit
}
}
}



This page is a thread posted to the opentalk forum at www.opentalk.org.uk and archived here for reference. To jump to the archive index please follow this link.

You can Add a comment or ranking to this page

© WELL HOUSE CONSULTANTS LTD., 2024: Well House Manor • 48 Spa Road • Melksham, Wiltshire • United Kingdom • SN12 7NY
PH: 01144 1225 708225 • FAX: 01144 1225 793803 • EMAIL: info@wellho.net • WEB: http://www.wellho.net • SKYPE: wellho